Easy help with fuel lines please

[slikside]

I'm in the process of rebuilding my Q-jet carb and thought it might be a good idea to install an inline fuel filter between tank and pump (lest all my hard carb work go down with debris!) I have 2 lines INTO my fuel pump and one line out of pump. Am I safe in assuming that since the line from pump to carb is 3/8", that the supply line TO the pump is also the 3/8" line? The other line TO pump is 1/4". Fuel filters tend to work best when the fuel is going in the right direction!

I've looked at my resources and couldn't find the answer. I figured this would be a softball Q for the knowledge base on this board!

Thanks for any help.

[cdowns]

best to have filter between the pump and carb

[Zoomin]

Originally Posted by slikside

I'm in the process of rebuilding my Q-jet carb and thought it might be a good idea to install an inline fuel filter between tank and pump (lest all my hard carb work go down with debris!) I have 2 lines INTO my fuel pump and one line out of pump. Am I safe in assuming that since the line from pump to carb is 3/8", that the supply line TO the pump is also the 3/8" line? The other line TO pump is 1/4". Fuel filters tend to work best when the fuel is going in the right direction!

I've looked at my resources and couldn't find the answer. I figured this would be a softball Q for the knowledge base on this board!

Thanks for any help.

To answer your question, yes, the larger line is the supply and the smaller is a return line. I installed a filter on the supply line and it works fine.

[slikside]

Yeah I guess I failed to include the word "additional" filter when refering to the in-line. I fully intend to run the filter in the carb as well. Too much junk in the filter housing lead me to rebuild the thing in first place (flooding out). Figured more frequent filter changes, and an additional one prior to pump for some insurance.

And thanks for the clarification on supply line! 'preciate it.

[Shyguy]

The fuel filter between the gas tank and fuel pump should be alright in the cooler weather, but may cause vapor lock problems in warmer weather.

On my 350 I put a metal fuel filter in the line in front of the passenger head and it worked great for many years.

[adpostel]

This is what Aeromotive recommended, it seems to work great, no pressure problems whatsoever....

[slikside]

Man, adpostel! If I put that filter system on my truck, it would be the nicest thing on it! Looks like something off a turbo-jet engine...........sweet. But your not running a stock, mechanical fuel pump with that set up, are you?

[Jacfourteen]

Originally Posted by slikside

your not running a stock, mechanical fuel pump with that set up, are you?

I would guess not, you can see his electric pump in the right hand side of the picture. Like others have said, its not a good idea to run a filter before the pump. It causes the pump to pull greater vacuum and leads to a lower boiling point of the gasoline, in hot weather the fuel can then boil and cause vapor lock.

[slikside]

Originally Posted by Jacfourteen

I would guess not, you can see his electric pump in the right hand side of the picture. Like others have said, its not a good idea to run a filter before the pump. It causes the pump to pull greater vacuum and leads to a lower boiling point of the gasoline, in hot weather the fuel can then boil and cause vapor lock.

Yes, well, I'm rather new to this........or rather, have been away such a long time that I was only recently aware folks were putting electrical fuel pumps in these rigs.

Anyhow, in the back of my mind I was wondering if there would be any adverse effects of running an inline filter b4 the pump and you have stated one. If I'm that concerned about junk in the fuel, maybe I should look at cleaning out the tank/lines as posted in another thread.

[Jacfourteen]

Originally Posted by slikside

Yes, well, I'm rather new to this........or rather, have been away such a long time that I was only recently aware folks were putting electrical fuel pumps in these rigs.

Anyhow, in the back of my mind I was wondering if there would be any adverse effects of running an inline filter b4 the pump and you have stated one. If I'm that concerned about junk in the fuel, maybe I should look at cleaning out the tank/lines as posted in another thread.

Sorry, I didn't mean it to sound harsh, I wasn't trying to be. Another thing that I thought of is maybe pull out your sender/pickup out of your tank and see if the inlet strainer is intact. It will stop most of the big stuff before it ever gets into your fuel lines. While your in there you can shine a light in the tank to assess what condition its in. Good luck, and let us know what you find out.